Golf balls?

[ShooterJM]

The air blast would ideally be spread evenly across the impact point on the paintball, but depending on design I don't know of if dimples would greatly change the structural integrity of a paintball. the more I research this the more I think that "dimples" aren't the answer. It has consistancy problems, extreme manufacturing issues, and cost effectiveness is highly doubtfull. Some step would have to be insterted after manufacturing and before the drying process I think.


EDIT: Was just thinking about this....perhaps instead of dimples a raised latticework? Could be applied in the rolling/drying process using modified driers.

BlackVCG -

I realize that this might be propriatary, but would there be a way to post the data of the nylon ball experiment on the data thread?

[Xerces]

well, dimples on a golf ball have to be in a certain geometric pattern to get the best lift, or whatever you call it. after looking at how rps makes theirs, it looks like they would have to make a completely different type of machine to make them, and to mass produce them with efficiency would drive the price up pretty well id imagine.

[ShooterJM]

Eh, working on that. Been in discussions with a manufacturer rep to see if the capabilities can be altered slightly. Gonna take some serious capital to set it up though, if it does work. That's why I'm really interested in AGD's test results. I need hard data, not theoretical calculations. Heck, just a source for nylon paintballs would be awesome!

[FatMan]

Originally posted by P8ntballerAK
OK, I went over this one with one of my friends who is a physics major. First of all a golf ball does not have to have a spin to launch like it does, hit one with a baseball bat and see. Second, a paintball with dimples would cause gaps between the barrel and the paintball which would let the air flow past the paintball and cause effeciency drop and would cause turbulance. And third, have you ever wondered why paintball are round instead of a bulletshape or anyother more aerodynamic shape? I will tell you why. If you have a sphere and apply pressure to one side the sphere will expand at all point equally untill resistans(the barrel) stops the side from expanding further. this keeps the pressure on a paintball equalized as much as possible. if you change the shape of the sphere lets say make it fimpled or make it like a bullet, you change the structural integrity of the entire object. if you try putting that much pressure on a bullet shaped object with the same size shell as on a paintball, it would explode. you could give it a thicker shell but that starts becoming more painful and dangerous. If put many dimples in a ball it will lose strength on the entire object so putting pressure on it would push the dimples out and then the ball would explode.

anyways
my .02$

Actually, empirical tests has shown that most of this lore is myth. Most paintballs already have a gap between them and the barrel - and the don't normally expand to fit the barrel. The round shape is to emable loading (as has already been stated). dimples probably wouldn't affect any of this. The issues probably come down to manufacturability versus actual performance gain.

FatMan

[mag-nanamus]

I had the same idea a couple years back. the golf ball paintball idea is even patented by someone. it would be interesting to talk with him to find out why he hasn't gone forward with this project.

[ShooterJM]

Originally posted by mag-nanamus
I had the same idea a couple years back. the golf ball paintball idea is even patented by someone. it would be interesting to talk with him to find out why he hasn't gone forward with this project.

The patent has expired. I called and checked. Yeah, I'm guessing the manufacturing expense Vs performance gain is what killed the idea from going into production.

[Miscue]

Problems:

Paintballs are only 3 grams = you need tons of spin.

Paintballs are filled with paint = viscocity of paint resists spin.

Paintballs are gelatin = hard to spin, hard to spin consistently, they have a hard enough time as it is keeping them round let alone round with dimples.

Paintballs already cost a lot of money... $1.00/paintball isn't gonna fly. :)

It won't be backspin if you tilt your gun.

Even if you could get them, I don't think they would help you.

[hostage]

Are these just theories? See i think it is a good idea it helps with golf balls, actually a golf ball was banned from the PGA, it had dimples on the outside and it had a ring going down the middle that was just flat. They put some putty around it then rapped a seranwrap around the ball and put it next to a heater to dry. Hey the ball preformed so well that they banned it from the PGA. BTW pleas make factual statements and just dont hypothize.
-Hostage

[aut911]

ok, if im not mistaken, an idea similar to the golf ball idea was thought of a while back during the initial testing of the flatline barrel. paintballs with tracks on them, the problem was that the tracks rarely lined up with the barrel the right way, so thats why (i believe) the flat line barrels bore is actually mottled. but my point is,a paintball will not fly farther or straighter due to its dimples set in a pattern, i think it will make a paintball less accurate and slow down faster, i might be totally wrong but i dont think so. the main thing paintball manufacturers should be worried about is consistency of paint size and shape than dimples.

no im not bashing anybodys ideas, im just giving my opinion, in a 16 year olds fashion.

thanks for reading

aut911

[ShooterJM]

I think we're combining two different issues. Spin and Dimpling. They're not neccesarily related.

[aut911]

the reason i put in the spin part is because of the way a golf club sends a golf ball flying, giving it backspin when it hits it, to give it a longer range, and the dimples are there to keep the ball from veering off into the bushes and staying on target. the problem with a paintball is that it is too light to carry spin for very long at all, thats partially why we see a flatline barrel have that really drastic drop in altitude, because alot of its energy was spent on that flat line trajectory. but for the coolness factor of the flat-line shootting paint without any arc is amazing.


aut911

i have no idea if this post makes any sense, i just woke up.

[ShooterJM]

Originally posted by aut911
the dimples are there to keep the ball from veering off into the bushes and staying on target. the problem with a paintball is that it is too light to carry spin for very long at al

well, dimples themselves, as far as my limted understanding goes, are only used to delay boundry layer seperation from the surface of the object in flight (in this case a golfball). By delaying the seperation the vacuum behind the object is greatly decreased allowing the object to fly further. As to the direction of the flight, as long as the dimpling is consistant the direction won't change. That's why if you have old paint that has a few dimples on it it tends to fly out of your barrel like a hummingbird on heroin. It's not uniform so the airflow changes.

The big question is would dimpling alone (sans any spin) cause enough effective distance gain to be worth the manufacturing costs?

[nerobro]

Dimples on a golf ball are about making the boundry layer stick to the ball longer. for a ball without spin you want the boundry layer to seperate as soon as it reaches the middle of the ball. But round objects cling to the boundry layer and wrap it around the back of the ball. That's what causes the buzzing you hear when a paintball flys by you. it's the boundry layer tearling off the paintball at different points and causing a wiggle in the paintballs path. (think the air behind a semi, but on a much smaller scale) Dimples will only cause this problem to worsen.

Dimples will cause a ball shot from a flatline to climb.. a LOT. But that's not the point of the flatline, the point of the flatline was to keep the ball level..... golf balls are much more dense items than paintballs can need all the lift they can get. Being such light items paintballs are difficult to compensate properly with lift. And at least from testing it looks like it's best to leave them NOT spinning at all, and smooth.

[CTG]

It's not the spin of the ball. Dimples on a paintball would be helpful, but not at speeds below 300fps.

[Skunk_werkes]

Originally posted by ShooterJM


well, dimples themselves, as far as my limited understanding goes, are only used to delay boundary layer separation from the surface of the object in flight (in this case a golf ball). By delaying the separation the vacuum behind the object is greatly decreased allowing the object to fly further. As to the direction of the flight, as long as the dimpling is consistent the direction won't change. That's why if you have old paint that has a few dimples on it it tends to fly out of your barrel like a hummingbird on heroin. It's not uniform so the airflow changes.

The big question is would dimpling alone (sans any spin) cause enough effective distance gain to be worth the manufacturing costs?

Your bang on :) , The purpose of dimples is thus: to create a very fine layer of turbulent air along the surface of the golf ball, the turbulent air actually has more friction then non-turbulent air and as such tends to 'stick' to the ball longer this delays the boundary layer separation and reduces the area of turbulent lower pressure air behind the ball. The main outcome of this is to reduce the pressure differential (well actually force differential... F=p*A) between the area in front and behind the ball. Quite simply; we know that the air in front of the ball is at a higher then atmospheric pressure, normally (without dimples) the boundary layer would separate just past middle and as a result you would have a large area at a lower pressure (relative to the air in front of the ball). I think everyone can figure out what happens with a high pressure in front and a lower pressure behind. The resultant force is acting opposite to the direction of travel, (it would slow the ball down). The dimples delay the boundary layer separation, reducing the area of low(er) pressure behind the ball, thus reducing the resultant force.
It's interesting to note that the slight increase in friction caused by the dimples is greatly outweighed by the benefits of increased boundary layer adhesion. A similar method can be seen in Formula 1 racing, the bulge (when viewed from the top) in the middle of the car is designed to prevent boundary layer separation. If done properly if yields a greater improvement then the negative effects of increasing cross sectional area.

Originally posted by nerobro

Dimples on a golf ball are about making the boundry layer stick to the ball longer. for a ball without spin you want the boundry layer to seperate as soon as it reaches the middle of the ball. But round objects cling to the boundry layer and wrap it around the back of the ball. That's what causes the buzzing you hear when a paintball flys by you. it's the boundry layer tearling off the paintball at different points and causing a wiggle in the paintballs path. (think the air behind a semi, but on a much smaller scale) Dimples will only cause this problem to worsen.